Healing pearl oysters with anti-bacteria virus an antibiotic-free alternative:Padma Shri Ajai Sonkar

New Delhi, Sep 24 (PTI) Bacteriophages -- viruses that target and kill specific bacteria -- present a natural method for healing pearl oysters after surgical implantation, while offering a sustainable and eco-friendly alternative to the use of antibiotics, marine biologist and Padma Shri recipient Ajai Kumar Sonkar has said.

Pearl oysters are surgically implanted to trigger the formation of a pearl, which makes use of an oyster's natural defence mechanism.

Experiments revealed that oysters immersed in seawater enriched with bacteriophage for 72 hours showed a significantly faster recovery from wounds, compared to those treated using antibiotics, according to a study abstract shared by Sonkar with PTI.

The bacteriophage-based technique of treating oysters also demonstrates how India can contribute towards shaping a sustainable and healthier future for aquaculture the world over, Sonkar said, addressing an audience at the 'Aquaculture 2025' conference conducted by the European Aquaculture Society in Valencia, Spain, during September 22-25.

"This study highlights the potential of bacteriophage therapy as a sustainable, environmentally friendly alternative to antibiotics in pearl oyster farming," the abstract states.

Further, a key advantage of the therapy is specificity, phages only targeted harmful bacteria, whilst keeping beneficial ones intact, it says.

The scientist added that while antibiotics have been indispensable to aquaculture for decades -- especially in delicate procedures such as pearl oyster surgery -- overuse has led to concerns about antibiotic resistance, ecosystem disruption, and food safety.

"This is the first public disclosure of a technology that heals marine oysters after surgery without antibiotics," Sonkar said.

"It demonstrates the strength of indigenous science from India and its potential to shape a sustainable and healthier future for global aquaculture," the marine biologist added.

Sonkar said the findings suggest a potential in reducing a reliance on antibiotics and addressing antimicrobial resistance, which is attracting urgent attention the world over.

The study "also directly supports the United Nations Sustainable Development Goals (SDGs), particularly those focused on sustainable food production, life below water, and responsible innovation," he said.

The scientist was recognised with the civilian award, a Padma Shri, in March 2022 for his contributions to the field of aquaculture, specifically in developing pearl-making techniques using tissue culture.

For the study, 400 surgically implanted oysters were divided into three groups: 150 immersed in seawater enriched with bacteriophage, 150 treated with antibiotics and exposed to oxytetracycline at a 1.5 parts per million concentration, and 100 maintained in untreated filtered seawater.

Phage-treated oysters recovered from wounds over a duration of 48-72 hours, while antibiotic-treated ones took 72-96 hours to recover.

Mortality in the former was found to be 5 per cent, "markedly lower compared to the antibiotic-treated group (12 per cent) and control group (18 per cent)," the abstract said.

An analysis of tissues revealed reduced inflammation and superior regeneration among the phage-treated oysters.

This innovation signals a transformative shift that could be extended to other aquaculture sectors, including finfish and shellfish farming, reducing the global dependency on antibiotics, Sonkar said. PTI RAB KRS RHL